Vacuum distillation apparatus



Dec. 18, 1951 c D, HlCKMAN 2,578,999

VACUUM DISTILLATION APPARATUS Filed April 14, 1948 4 Sheets-Sheet 1ATTORNEYS INVENTOR. KEN/Vi? 0.0. H/GKMA/V BY Dec. 18, 1 9 K. c. D.HICKMAN 2,578,999

VACUUM DISTILLATION APPARATUS Filed April 14, 1948 4 Sheets-Sheet 2INVEN TOR. KENNETH G 0. HI GKMAN ATTORNEYS 7 Dec. 18, 1951 K. c. D.HICKMAN 2,578,999

VACUUM DISTILLATION APPARATUS Filed April 14, 1948 4 Sheets-Sheet 3 u uI .7 74 I H76 73 (J u it; 78 I 6ml. 92

FIG. 5

INVENTOR. KE/V/VE TH a. a H/GKMAN I /fiamz/f Zd 414. fi/mJ/rm 4 98ATTORNEYS Dec. 18, 1951 K. cQn. HICKMAN 2,573,999

VACUUM DISTILLATION APPARATUS Filed April 14, 1948 4 Sheets-Sheet 4ROTOR HEATE R n- E 3 B- bl O u a: E

INVENTOR. KENNET G D. h! GKMA/V M wad-1 ATTORNEYS Patented Dec. 18, 1951UNITED STATES PATENT 1 OFFICE VACUUM DIS'TILLATION APPARATUS Kenneth C.D. Hickman,

Rochester, N. Y., as-

signor, by mesne assignments, to Eastman Kodak Company, Rochester, N.Y., a corporation of New J ersy This invention relates to vacuumdistillation apparatus and especially to high-vacuum unobstructed-pathdistillation apparatus embodying a centrifugal evaporator.

It is a principal object of the invention to pror, vide simplifiedvacuum distillation apparatus of the centrifugal type which shall besubstantially less expensive than such apparatus heretofore availablewhile at the same time retaining all functions essential to effectivedistillation.

It is a further object of the invention to provide more compact and moreefficient vacuum distillation apparatus of the centrifugal type.

Another object is to simplify high-vacuum unobstructed-path distillationapparatus and 1.5 processes employing centrifugal evaporators byeliminating the necessity for external reservoirs for distilland withtheir concomitant extra cost and attendant multiplicity of conduitsextending through the walls of the vacuum chamber.

It is a further object of the invention to provide a self-contained unitcomprising all the essential elements of a centrifugal high-vacuum stillwhile avoiding in large measure complex and expensive structuralfeatures.

The invention also aims toprovide novel distillation apparatus of thehigh-vacuum unobstructed-path type employing a centrifugalevaporator inwhich distilland is stored, distilled, and condensed all within a singlevacuum chamber.

More specifically, the invention aims to provide such apparatus in whichthe walls of the vacuum chamber itself provide a reservoir fordistilland within the chamber. 35

A further specific object of the invention is to minimize the number ofjoints in the vacuum chamber of ahigh-vacuum centrifugal still andthereby to minimize danger of leakage.

The invention further aims to provide a more 40 efiicien't heatingarrangement for centrifugal evaporators in vacuum distillationapparatus.

A further specific object of the invention is to provide a compact andreadily portable unit efficiently combining in a self-containedstructure apparatusfor effectively carrying out molecular distillationoperations on a small scale and which shall be especially adapted forlaboratory and experimental use.

The invention further aims to provide novel 50 distillation apparatuscapable of being disassembled for cleaning with a minimum of time andeffort.

A further specific aspect of the invention aims to provide suchapparatus designed for ready 5:;

cleaning between successive runs by a simple removal of a single belljar member forming the vacuum chamber and without disturbing the rest ofthe apparatus.

The invention further aims to provide simple and effective control meansfor vacuum distillation apparatus.

More generally, the invention aims to provide simple, economical, andefficient procedures and apparatus for high-vacuum distillationemploying a centrifugal evaporator andan opposed condensing surfaceseparated from the evaporator by substantially unobstructed space andparticularly to provide such apparatus which shall be neat, compact,readily constructed, readily assembled, and readily disassembled.

The manner in which these and other objects of the invention areattained will be apparent from the following description taken inconjunction with the accompanying drawings and the appended claims.

In the accompanying drawings;

Fig. 1 represents a partially broken and partial cross-sectional frontview of apparatus embodying the present invention in a preferred form.

Fig. 2 is a' partially broken and partial crosssectional side view ofthe apparatus of Fig. 1.

Fig. 3 is an enlarged sectional view of the commutator apparatus of Fig.2;

Fig. 4 is a top view of the apparatus of Figs. 1 and 2.

Fig. 5 is an enlarged fragmentary front View partially in sectionshowing the driving means for the pump and rotor.

Fig. 6 is a view partially in section of the pump.

Fig. '7 is a sectional view taken along line i"--'! of Fig. 6.

Fig. 8 is a wiring diagram of the apparatus.

Referring to the drawings, numeral I'll: designates a base support forthe apparatus. Control panel 12 is rigidly attached to base support iil.Baseplate I4 extends beyond control panel l2 and is held rigidly inposition by the housing of control panel l2. Milliammeter It on control5 panel I2 is connected to thermocouple It and is used to determine thetemperature of the rotor. Meter 20 on control panel [2 is connected toPirani tube 22 (Fig. 8) in the vacuum chamber and is used to determinepressure. Autotransformer control 24 on control panel I2 is used to varythe heat in diffusion pump 26- (Fig. 8). Autotransformer control 28 oncontrol panel 12 is used to varythe current flowing in the rotor heatingelement. Control switches 30', 32, 34; and 35 on control panel I?operate respectively the r 3 mechanical fore pump, the diffusion pump,the rotor, and the rotor heater. Each of pilot lights 38 on controlpanel l2 lights up when the control switch in its circuit is turned on.

Baseplate I4 supports all of the operating parts of the apparatus exceptthe evacuating system which is not shown. Controls for the diffusionpump and fore pump are placed on control panel I2 for the sake ofconvenience.

Extending downward from baseplate I4 is a rigid hollow metal post 48.Post 46 supports bearings 42 and 44 through which hollow shaft 46 of therotor commutator passes. Rotor 48 is attached to hollow shaft 46. Rotor48 is hollow and contains an embedded heating element 59 which isintegral therewith and which rotates with rotor 48. Leads 52 fromheating element 58 pass through hollow shaft 46 to slip rings 54 and 56between which there is provided insulating material H. Contact with sliprings 54 and 55 is made by metal strips 58 and 66 which are fastened toa piece of nonconducting fibrous material designated as numeral 62.Metal strips 58 and 68 are attached to terminals 64 and 66. These leadsare connected to autotransformer 28. By embedding the heating element inthe rotor, variations in temperature between the vaporizing surface andthe reverse'face of the rotor are minimized with the result thatobjectionable carbonization heretofore encountered on the reverse faceis substantially reduced if not entirely eliminated. However, if thisfeature should be considered unnecessary, the heating element need notbe embedded in the rotor. If placed behind the rotor it will function asa radiant heater.

Pulley 68 is rigidly attached to hollow shaft 46. Spring belt I6 drivespulley 68. Spring belt 19 is impelled by pulley 12 which is attached toshaft 14 at a point near the top of the interior of gas-tight turret I6on top of baseplate I4. A bevel gear drive or worm gear drive or othersuitable, mechanical drive may be used in place of the belt drive shown.Shaft 14 passes through gas-tight bearing I8 to the outside of thevacuum chamber where it is connected to motor 80 by means of flexiblecoupling 82.

Worm 84 is attached to shaft I4 and serves to rotate gear 86 whichrotates shaft 96 to which gear 92 is rigidly attached. Gear 86 is easilyremovable and may be replaced by a different size of gear where it isdesired to change the speed of rotation of shaft 98. Gear 92 meshes withgear 94 on shaft 96 which rotates inside housing 98 through gas-tightbearing II. Gear pump I3 is attached to the base of housing 98 andservesto lift distilland to the level of rotor 48. Gears I and I! ofpump I3 are actuated by shaft 96. Other pumping arrangements such as. acentrifugal pump or chain hoist may be used in place of gear pump I3.

A small receptacle I9 is attached to housing 98. Receptacle I9 serves asa pickup for undistilled residue. It may be emptied into the bottom ofbell jar 39 by lifting ball 2| which is attached to pull-up controlmeans 23 by a fine wire (not shown). If desired, a second receptacle maybe placed below receptacle I9 and pump I3 may be designed to pump fromthis receptacle rather than the bottom of bell jar 39.

When pump I3 is in operation, distilland is forced upward through theannular space between housing 98 and rotating shaft 96 until it reachesT-connection 25 at a point just above 0 which feeds onto the center ofrotor 48.

4 rotor 48. Feed conduit 21 leads from T-connection 25 to theapproximate center of rotor 48.

Receptacle 8|, located on the upper side of baseplate I4, communicateswith conduit 83 Receptacle 8| may be closed by actuating screw clamp 85.

In operation, receptacle 8| is used when it is desired to employ theapparatus as a degasser. Liquid fed into receptacle 8| passes directlyto rotor 48 where it is degassed, the residue passing to receptacle I9where it may be held in readiness for further treatment.

Surrounding the periphery of rotor 88 are annular baflles or gutters 29,3|, and 33. These bafiles serve to collect and guide undistilled residuefrom rotor 48 to receptacle I9, the residue beingpicked up by gutter 29,from which it flows by gravity to gutter 3|, thence to gutter 33, andfrom there to receptacle I9. In passing from gutter 33 to receptacle I9,the residue may be cooled by contact with cooling pipe 35. Coolin pipe35 enters the system through baseplate I4 and makes a single pass downone side of metal post '46, then curves over to a point under thespillway of gutter 33, then returns and passes'up the other side ofmetal post 48. In this way cooling pipe 35 not only cools the residuepassing to receptacle I9 but also cools bearings 42 and 44.

Extending downward from baseplate I4 and entirely surrounding pump I3,receptacle [9, and rotor 48, is removable bell jar 39 formed of rigidmaterial such as fairly heavy glass. In the event transparency forobservation purposes is not desired, the bell jar may be formed of metalor other suitable material. Bell jar 39, which is supported byadjustable clamp member 13, makes gas-tight connection with baseplate I4through gasket 4|. Slightly bulbous surface 43 of bell jar 39 serves asa condensing surface. At the bottom of bulbous surface 43 is collectinggutter 45 which picks up condensed distillate. Condensed distillate maybe drawn off through stopcock 41 or may be returned to the distilland asreflux through return pipe 5|.

The bottom of bell jar 39 has sump 53 to contain pump I3. Distilland maybe introduced to this sump through conduit 55.

Bell jar 39 may be evacuated by pumping means (not shown) connected withconduit 6| which opens into the vacuum chamber through the plate I4.Microswitch 63 (Fig. 8) prevents the circuit of heating element 50 frombeing closed until a low degree of pressure has been attained.

In operating the apparatus shown in the drawings, bell jar 39 is set inplace and the evacuating system placed in operation. While theevacuating system is not part of the self-contained unit, controlswitches for it are located on panel I2 and it is only necessary toconnect the electrical leads 15 from the pumping system to terminals TIon control panel I2 in order to adjust the entire apparatus by means ofcontrol panel l2.

After the pressure has been reduced, toggle switch 34 is turned to onposition and motor thereupon actuates rotor 48 and pump I3. Rotor heaterswitch 36 is turned on'and the heat input adjusted by means ofautotransformer 28. Distilland is now allowed to enter pump 53 throughconduit 55. Pump I3 raises the distilland to T-connection 25 from whichit is fed to rotor 48 by feed conduit 21. Distilland which isvaporizedon the vaporizing surface of rotor 48 condensed; on theair-coIedLsurface, 4.3 of bell jar 39 from which itfiows by-gravity tocollecting;

gutter 45.

Undistilled residue from, the vaporizing surface of rotor 48" is pickedup by gutter 29,, and passed through gutters 3i: and 33 to: receptacle19. During the starting period ball 2] is usually held up so thatreceptacle l9- empties into sump 53,, but as soon as the apparatus isproperly adjusted, ball 2!. is, lowered by means of pull-up means 23 andreceptaclev 19, then starts tofill.

Although features of the apparatus are applicable generally tocentrifugal. vacuum stills, the particular unit shown and described isespecially adapted for small scale use in the laboratory. Witha rotorthe apparatus weighsless than one hundred pounds and is thus easilyportable.

While the invention has been described in considerable detail withreference to certain structures, procedures, and materials, it will beunderstood that modifications and variations therein may be effectedwithout departing from the spirit and scope of the invention as. it isdefined by the appended claims.

What I claim is:

1. Vacuum distillation apparatus comprising a self-contained portableunit adapted to be readily moved from place to place, said unitcornprising an lip-standing column, a supporting member projectinglaterally outward from said column at an elevated position and having alower face formed to provide a wall of a Vacuum chamber, a jar-likemember of elongated configuration arranged in depending relation to saidsupporting member with the mouth of said jarlike member in sealingengagement with said face and forming a gas-tight vacuum chamber thereiwith, conduit means communicating with said chamber through said walland being adapted to be connected with vacuum producin apparatus forevacuating said chamber, a conical diskshaped vaporizing member, meansdepending from said wall and rotatably supporting said vaporizing memberwithin said vacuum chamber with the vaporizing surface of said memberdisposed adjacent a side wall portion of said jar and being separatedtherefrom by substantially unobstructed space, a motor mounted outsidesaid chamber on said supporting member, power transmitting meansextending through said wall and operably connecting said motor and saidvaporizing member for rotating said member, electrical heating meansassociated with said diskshaped vaporizing member for heating thesurface thereof to distilling temperatures, said jarlike memberproviding a reservoir for liquid distilland at the bottom thereof, apump and communicating conduit means carried by said supporting memberand arranged within said vacuum chamber to transfer distilland from saidreservoir to said vaporizing member, said side wall portion of saidjar-like member opposite said vaporizing surface being outwardlydeformed and providing an air cooled condensing surface, said side walladjacent a lower portion of said condensing surface being provided withcondensate-collecting and discharging means, and control devices carriedon said up-standing column includin controls for said motor, controlsfor said vacuum producing means, controls for said heating means and aninstrument adapted to indicate the degree of vacuum within said chamber.

2. Vacuum distillation apparatus comprising wall means forming a vacuumchamber, said wall ber, a rotatable conical disk-shaped vaporizingmember mounted: within said chamber in distilling relation to saidcondensing surface, heat-= ing, means including an electricalresistanceheat ing, element enclosed withinsaid rotatable vaporizingmember and arranged to rotate with said vaporizingmember and meansiforenergizing said element, means for evacuating said chamber, means fordriving said vaporizing membergliquid-conveying means arranged whollywithin said chamber and extending from said reservoir to said vaporizingmember for progressively transferring distilland from saidtreservoirtosaid vaporizing member, andresidue-collecting means associated withsaid vaporizing member arranged to collect undistilled residue afterpassage along said vaporizing member.

3. Vacuum distillation apparatus comprising an up-standing column, asupportng member projecting laterally outward from said column at anelevated position and having a lower face formed to provide a wall of avacuum chamber, a bell jar arranged in depending relation to saidsupporting member and having the mouth of said bell jar in sealingengagement with said lower face and forming a gas-tight chambertherewith, said bell jar comprising a side Wall merging downwardly witha generally concave closed end, said closed end forming a reservoir fordistilland, a localized portion of said closed end being recessed belowthe remainder of said closed end and forming a distilland-collectingsump, a side wall portion being outwardly deformed and providing acondensing surface, a rotatable generally plate-like vaporizing memberin said chamber and being supported from said supporting member, saidvaporizing member being disposed with the vaporizing surface opposed tosaid condensing surface, pump and conduit means within said chamber andarranged to progressively convey distilland from said sump onto saidvaporizing member, means for collecting and removing condensate fromsaid condensing surface, means for driving said vaporizing member andsaid pump, and means for evacuating said chamber.

4. Vacuum distillation apparatus comprising a vertically disposedgenerally tubular member having a concave closed lower end and an openupper end, said concave closed lower end forming a reservoir fordistilland, plate means closing the upper end of said tubular member,said plate means and said tubular member combining to form a vacuumchamber, means for evacuating said vacuum chamber, a conical disk-shapedvaporizing member, means depending from said plate means and rotatablysupporting said vaporizing member within said vacuum chamber with thevaporizing surface of said vaporizing member disposed adjacent an upperwall portion of said tubular member and being separated from said upperwall portion by substantially unobstructed space, means for rotatingsaid vaporizing member, said upper wall portion of said genervoir tosaid vaporizing member.

5. Vacuum distillation apparatus comprising wall means forming a vacuumchamber, said wall means comprising generally tubular side wall means, agenerally concave closed lower end portion integrated with said sidewall means and forming with said side wall means a generally jar-likemember, and removable plate means closing the mouth of said jar-likemember and being arranged in sealing relation therewith, said closedlower end portion providing a reservoir for distilland, a localizedportion of said side wall means being outwardly deformed and forming acondensing surface within said chamber, a lower portion of saidcondensing surface forming a condensate-collecting gutter, a conicaldiskshaped vaporizing member disposed within said chamber in distillingrelation to said condensing surface, means for rotatably mounting saidvaporizing member in dependent relation to said plate means, means forevacuating said chamber, heating means for said vaporizing member,

means for rotating said vaporizing member,

pumping and communicating conduit means within said chamber andextending from said reservoir .for distilland to said vaporizing memberfor progressively transferring distilland from said reservoir to saidvaporizing member, annular gutter means arranged about the periphery ofsaid vaporizing member for collecting undistilled residue from saidvaporizing member, and container means arranged to receive residue fromsaid annular gutter means.

KENNETH C. D. HICKMAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

, UNITED STATES PATENTS Number

